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Updated: Mar 19, 2026

Molten-Salt Synthesis of Complex Metal Oxide Nanoparticles
Published on: October 27, 2018
Elaboration, étude structurale et analyse CHARDI et BVS d'une nouvelle variété β-Na9Cr(MoO4)6 de type alluaudite
Manel Sonni1, Riadh Marzouki1, Mohamed Faouzi Zid1
1Laboratoire de Matériaux et Cristallochimie, Faculté des Sciences de Tunis, Université de Tunis El Manar, 2092 Manar II Tunis, Tunisia.
Abstract:
The title compound, nonasodium chromium(III) hexakis[molybdate(VI)], β-Na9CrMo6O24, was prepared by solid-state reactions. This alluaudite-type structure is constituted of infinite layers formed by links between M 2O10 (M = C/Na) dimers and MoO4 tetra-hedra. The Na(+) and Cr(3+) cations are located in the same site with, respectively, 0.25 and 0.75 occupancies. The layers are connected to each other through MoO4 sharing corners, resulting an in open three-dimensional framework with hexa-gonal-form cavities occupied by Na(+) cations. The proposed structural model is supported by charge-distribution (CHARDI) and bond-valence-sum (BVS) analysis. All atoms are on general positions except for one Mo, two Na (site symmetry 2) and another Na site (site symmetry -1). A comparison is made with the similar structures Na4Co(MoO4)3, Na2Ni(MoO4)2, Cu1.35Fe3(PO4)3 and NaAgFeMn2(PO4)3.
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